Automatic workshop AGV intelligent transfer system

Abstract

The invention discloses an automatic workshop AGV intelligent transfer system, and relates to the field of material transfer automatic control. The invention aims to solve the problem that an existing workshop material transfer method is high in error rate in the transfer process. The method comprises the following steps: receiving a task information character string sent by a workshop control center and analyzing the task information character string; obtaining an AGV scheduling scheme based on a workshop data twinborn model; a task instruction is generated according to the task information character string analysis result, the task number and the flying bar number in the skip car state data table and the task execution information JSON format, and the task instruction is sent to the AGV control system; and the AGV control system feeds back a task execution state and AGV position data, and writes the task execution state and the AGV position data into the skip state data table and the AGV state data table. The AGV material transfer device is used for achieving AGV material transfer in the workshop.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automatic control, in particular to an AGV intelligent transfer system for an automated workshop. BACKGROUND

[0002] With the popularization and application of industrial 4.0 technologies represented by industrial robots, AGVs and information platforms, the automation level of the workshop has been greatly improved. With the popularization of automated production equipment in the workshop, higher requirements are put forward for the logistics transfer of the workshop. It is a key element to promote the development of new productivity represented by unmanned workshops and black-light factories to open up the information transmission channel between heterogeneous automation platforms in the workshop and form an efficient and intelligent logistics transfer system.

[0003] Automated production lines, AGVs and other intelligent devices have been widely used in the production process of automated workshops. Different automated devices in the automated workshop have a special control system. In order to enable the operator to accurately obtain the device running status and control the production rhythm, the workshop develops a special workshop control center information platform. However, the heterogeneity between the AGV control system and the automated production line control system makes it difficult to realize the timely interaction of information, and the key workshop logistics is difficult to realize intelligent transfer.

[0004] The current workshop relies on workers to participate in material handling, equipment production task assignment and automated production line feeding and discharging links, acting as a "lubricant" for the automation of the workshop. However, this method requires the operator to be proficient in the interactive process of AGVs, production equipment and other automated devices in the entire production process. At the same time, the frequent feeding and discharging process of multiple automated production lines will increase the workload of the operator, which may easily cause fatigue and misoperation of the worker, resulting in a high failure rate in the transfer process. SUMMARY

[0005] The present application aims to solve the problem of high failure rate in the transfer process of the existing workshop material transfer method, and proposes an AGV intelligent transfer system for an automated workshop.

[0006] An AGV intelligent transfer system for an automated workshop includes a system interface module, a task generation module, a data management module and a production line communication module. The system interface module includes a workshop control center API interface and an AGV control system API interface. The workshop control center API interface is used to receive the task information string sent by the workshop control center and send the task information string to the task generation module. The workshop control center API interface is used to receive the task completion information fed back by the task generation module when the AGV task is completed, and send the task completion information to the workshop control center. The AGV control system API interface is used to receive task instructions and send them to the AGV control system. It also receives the task execution status and AGV position data fed back by the AGV system and sends them to the data management module. The task generation module is used to parse the task information string, receive the AGV scheduling scheme, convert the AGV scheduling scheme into the task execution information JSON format, read the task number and flyer number from the material car status data table, generate task instructions using the task information string parsing result, the task number and flyer number from the material car status data table, and the task execution information JSON format, and send the task instructions to the AGV control system API interface of the system interface module. The task generation module is used to read the information in the AGV status data table, and determine whether the AGV has arrived at the production line and whether the AGV task has been completed based on the information in the AGV status data table, and send signals to the production line communication module, workshop control center API interface or data management module. The task generation module is used to read the production line feedback information obtained by the production line communication module, generate a continue task instruction based on the production line feedback information, and send the continue task instruction to the AGV control system API interface. The data management module includes database interface tools and a digital twin model; The database interface tool is used to receive task execution status and AGV position data, and write the task execution status and AGV position data into the material car status data table and the AGV status data table. The workshop digital twin model obtains the AGV scheduling scheme and sends the AGV scheduling scheme to the task generation module; The production line communication module is used to establish a communication link between the automated workshop AGV intelligent transfer system and the automated production line control system, sending queries to the automated production line control system and receiving feedback.

[0007] Furthermore, the task information string is a 2-level nested JSON string, including: task number, request time, and parameter information. The parameter information includes FIBA ​​number, production line number, material cart number, material cart position coordinates, material cart direction, task template number, target position coordinates, and process number. The task completion information is a JSON string that includes a task completion flag, AGV number, and task number.

[0008] Furthermore, the task execution status reported by the AGV system includes: AGV number, AGV position coordinates, task number, material handling vehicle number, AGV direction, position coordinates, material handling vehicle direction, task execution status, and message number.

[0009] Furthermore, the parsed task information string results include: task type and task parameters; The task parameters include: Flyer number, production line number, task type, and material car number; The task execution information in JSON format includes: AGV number, task type, task target location, travel route, and task priority.

[0010] Furthermore, the task generation module is used to read information from the AGV status data table, determine whether the AGV has arrived at the production line and whether the AGV task has been completed based on the information in the AGV status data table, and send signals to the production line communication module, the workshop control center API interface, or the data management module, specifically: First, determine whether the AGV has reached the production line. If it has, send a signal to the production line communication module; if the AGV has not reached the production line, send a signal to the data management module. Then, it is determined whether the AGV task is completed. If the task is completed, a task completion string is generated and sent to the workshop control center API interface; if the task is not completed, a signal is sent to the data management module.

[0011] Furthermore, the production line feedback information includes: permission to enter and permission to leave; The continuation task instruction includes: AGV number and task number; The types of task instructions include: production line material feeding task instructions, production line material feeding task instructions, material cart transfer task instructions, scooter return task instructions, and material cart binding task instructions; The task instruction content includes: task number, map number, task type, location path, AGV number, material vehicle number, and request number; the material vehicle binding task instruction includes: request number, material vehicle number, AGV number, material vehicle location coordinates, material vehicle direction, and material vehicle binding flag; The location path includes: coordinates of the production line task point, coordinates of the production line material inlet, and coordinates of the target location.

[0012] Furthermore, the material cart status data table includes: material cart task, material and location information, including material cart number, flyer number, material cart location coordinates, task number, material cart direction, storage location and production line number; The AGV status data table includes: AGV task, status and location information, including: AGV number, AGV status, task number, IP address, battery level, material handling vehicle number, AGV direction, location coordinates, material handling vehicle direction, task execution status, task execution steps and message number; The task execution steps in the AGV status data table include 1, 2, and 0; Where 1 indicates that the AGV transport vehicle has arrived at the production line position, 2 indicates that the AGV transport vehicle has entered the production line and reached the material inlet, and 0 indicates that the AGV transport vehicle has left the production line material inlet and reached the target position coordinates.

[0013] Furthermore, the production line communication module includes: a TCP communication client; Sending queries to the automated production line control system includes: production line communication polling and production line querying; The production line communication polling specifically involves the TCP communication client sending heartbeat communication codes to the automated production line control system at fixed time intervals, and then receiving feedback from the automated production line control system. a. If the production line communication module receives a heartbeat communication code from the automated production line control system, it means that the production line communication module and the automated production line control system have not lost connection. After waiting for the preset interval, the heartbeat communication code will be sent again. b. If the production line communication module does not receive the heartbeat communication code from the automated production line control system, it means that the production line communication module is disconnected from the automated production line control system. The initialized TCP communication client will attempt to connect to the production line TCP communication server. The production line query is sent to the automated production line control system, and the production line communication module also receives feedback information from the automated production line control system. The production line inquiry includes: production line entry inquiry, production line entry report, production line exit inquiry, and production line exit report information.

[0014] Furthermore, the production line inquiry includes: production line entry inquiry, production line entry report, production line exit inquiry, and production line exit report information, specifically: When the AGV material transport vehicle arrives at its designated location on the production line, the TCP communication client sends an entry query communication code to the automated production line control system, and then receives feedback from the automated production line control system: a) If the production line communication module receives a permission to enter the production line communication code from the automated production line control system, it sends the production line feedback permission to enter information to the task generation module. b) If the production line communication module receives a waiting entry communication code from the automated production line control system, it will wait for a preset time interval and then send the entry inquiry communication code again. When the AGV material handling vehicle enters the production line and reaches the material inlet, the TCP communication client sends an "Entered Production Line" report communication code to the automated production line control system. After waiting for a preset time interval, it sends a "Left Production Line" inquiry communication code to the automated production line control system and then receives feedback from the automated production line control system. (a) If the production line communication module receives a permission to leave the production line communication code from the automated production line control system, it sends the production line feedback permission to leave information to the task generation module. (b) If the production line communication module receives a waiting to leave the production line communication code from the automated production line control system, it will wait for a preset time interval and then send the leaving production line inquiry communication code again. When the AGV material handling vehicle leaves the production line and arrives at the material outlet, the TCP communication client sends a report communication code indicating that it has left the production line to the automated production line control system. The TCP communication client sends a 148-bit string of numbers to the automated production line control system, including: message header, function bits, task number, AGV number, reserved bits, and batch number. The message consists of: heartbeat communication code, entry inquiry communication code, entry report communication code, exit inquiry communication code, and exit report communication code. The function bit of the heartbeat communication code is 0, the function bit of the production line inquiry communication code is 1, the function bit of the production line entry report communication code is 2, the function bit of the production line exit inquiry communication code is 3, and the function bit of the production line exit report communication code is 4. The TCP communication client receives a 145-bit string of numbers from the automated production line control system, including the heartbeat communication code, permission to enter the production line communication code, waiting to enter the production line communication code, permission to leave the production line communication code, and waiting to leave the production line communication code. This string includes: message header, production line status bit, reserved bit, acknowledgment bit, interval bit, FIP number, and batch number. The response bit of the heartbeat communication code is 0, the response bit of the allow-to-enter-the-production-line communication code and the allow-to-leave-the-production-line communication code is 1, and the response bit of the wait-to-enter-the-production-line communication code and the wait-to-leave-the-production-line communication code is 2.

[0015] Furthermore, the workshop data twin model in the data management module is used to obtain the AGV scheduling scheme, specifically as follows: A1. Construct the objective function and constraints, specifically as follows: The objective function is to minimize the total travel distance of the AGV in completing all tasks; The constraints include: load constraints, material cart demand constraints, and power constraints; The load constraint is that the AGV's load capacity is less than a preset load limit; The material cart requirement constraint is that one material cart can only load and unload materials for one production line. The power constraint is that the AGV's power is greater than the power required to complete the task; A2. Initialize the iteration round t=1, initialize the population size N, the maximum number of iterations T, and set the elite ratio. ; A3. Randomly generate N AGV scheduling schemes based on the constraints. Each AGV scheduling scheme is treated as an individual, forming a population. ; The scheduling scheme includes: task execution order, AGV number assigned to the task, material car number transported by the AGV, and AGV travel path information; A4. Population Each scheduling scheme is input into the workshop data twin model for simulation, thereby obtaining the logistics scheduling results; The logistics scheduling result refers to the travel path of the AGV to complete the task; A5. Obtain based on logistics scheduling results The fitness value of each individual is calculated, and excellent individuals are selected based on their fitness values, generating a probability matrix: First, The objective function value of the scheduling scheme corresponding to each individual is used as the fitness value of each individual; Then, sort all individuals according to their fitness values ​​from smallest to largest; Finally, take the former. Each individual is considered an excellent individual. The probability of the excellent individual's task allocation and path selection is calculated to generate a probability matrix. A6. Random sampling is performed in the probability matrix to generate N new individuals to form a new population. Random sampling is then performed in the new population. Individuals, will Individuals and A population is composed of outstanding individuals. ; A7. Obtaining the Population The fitness value of each individual is determined, and the individual with the minimum fitness value is selected as the population. To obtain the optimal individual population to population The fitness value corresponding to the best individual in each population is determined. If the number of consecutive individuals with the same fitness value exceeds L, it indicates that the current fitness value has converged, and the result is output. The best individual in the list is selected as the optimal scheduling scheme; otherwise, A8 is executed. The fitness value of an individual is the objective function value of the scheduling scheme corresponding to the current individual; A8. Determine if the iteration number t is equal to T. If t is less than T, set t = t + 1 and return to A4; if t = T, output... The optimal individual in the pool is used as the AGV scheduling scheme; The workshop data twin model is constructed in the following way: First, create the workshop layout in Siemens PlantSimulation software; The workshop layout includes: all AGV running paths, the location of automated production lines, the location of material loading points on the production lines, the material storage area, the location of unloading points, and the distances between path points; Then, the AGV is modeled: The attributes of the virtual AGV are set according to the AGV's operating speed, load capacity, battery capacity, shape, size, and position angle parameters to ensure that the behavior of the virtual AGV is consistent with that of the physical AGV. Finally, the automated production line and material cart elements are modeled, and the relationship between the virtual AGV and the automated production line and material cart model is established to obtain a workshop data twin model. The elements of the automated production line include: material inlet position and angle attributes, and material inlet shape and size attributes; The material cart elements include: material cart shape and size, and material cart position and angle; The specific relationship between the virtual AGV, the automated production line, and the material cart model is as follows: when the AGV transports the material cart into the material inlet of the automated production line, the direction of the material cart model is set to be consistent with the direction of the material inlet; at the same time, the material cart model is set as a material cart used to transport materials for the current production line.

[0016] The beneficial effects of this invention are as follows: This invention enables information interaction between the workshop control center, the automated production line control system, and the AGV control system, allowing for intelligent transfer of AGV transport vehicles and materials between workshop production units. It achieves seamless coordination of information flow, task flow, and material flow within the workshop. This invention solves the communication and control challenges between heterogeneous automated production equipment at the system level, controlling AGVs to intelligently complete material transfer, on-line loading, and off-line loading within the workshop. This reduces the workload of workshop operators, improves the workshop's intelligence level, and avoids errors in the transfer process caused by employee fatigue and misoperation, thus reducing the error rate. Operators do not need to be proficient in operating different automated equipment; they can simply monitor the workshop's logistics status and issue material transfer tasks through the workshop control system, improving material flow efficiency and workshop management. This invention adds a workshop digital twin model to the data management module, updating AGV location and status information in real time. Based on EDA algorithms, it plans AGV scheduling schemes, further optimizing AGV scheduling efficiency and accuracy, and enhancing the performance and intelligence of the entire workshop intelligent transfer system. Attached Figure Description

[0017] Figure 1 This is a functional architecture diagram of the present invention; Figure 2 This is a flowchart of the production line interaction process; Figure 3 This is a flowchart of the task execution process; Figure 4 Flowchart for TCP communication initialization and heartbeat communication of the production line communication module; Figure 5 Flowchart for the workshop data twin model. Detailed Implementation

[0018] Specific implementation method one: as follows Figure 1 As shown, this embodiment of an automated workshop AGV intelligent transfer system includes: a system interface module, a task generation module, a data management module, and a production line communication module; The system interface module includes: a workshop control center API interface and an AGV control system API interface; The workshop control center API interface and AGV control system API interface of the system interface module are HTTP protocol communication interface programs written in JAVA language; The workshop control center API interface is used to receive task information strings sent by the workshop control center and send the task information strings to the task generation module. The workshop control center API interface is used to receive task completion information from the task generation module when the AGV task is completed, and then send the task completion information to the workshop control center. The task information string is a 2-level nested JSON string, including task number, request time and parameter information. The parameter information includes FIBA ​​number, production line number, material cart number, material cart position coordinates, material cart direction, task template number, target position coordinates and process number. The task completion information is a JSON string including a task completion flag, AGV number, and task number; The AGV control system API interface is used to receive task instructions generated by the task generation module and send the task instructions to the AGV control system. At the same time, it receives the task execution status and AGV position data fed back by the AGV system and sends the task execution status and AGV position data to the data management module. The task execution status reported by the AGV system includes: AGV number, AGV position coordinates, task number, material handling vehicle number, AGV direction, position coordinates, material handling vehicle direction, task execution status, and message number; In the system interface module, both the workshop control center API interface and the AGV control system API interface send JSON-formatted strings via HTTP POST, using service port 7070. The workshop control center is a customized workshop digital management platform; the automated production line control system is the host computer program responsible for controlling the PLC of the automated production line; the AGV control system is a Hikvision RCS2000 control system, controlling MR-Q7-1000CE-D2(M) stealth transport robots. The system interface module uses the POST method in the HTTP communication protocol to write the JSON-formatted string to be transmitted into the POST message body and send it, while simultaneously reading the JSON-formatted string from the received message body.

[0019] The task generation module is used to parse the task information string, receive the AGV scheduling scheme, convert the AGV scheduling scheme into the task execution information JSON format, read the task number and flyer number from the material car status data table, use the task information string parsing result, the material car status data table and the task execution information JSON format to generate a JSON format task instruction that meets the instruction requirements of the AGV control system, and send the task instruction to the system interface module (AGV control system API interface). The parsed result of the task information string includes: task type and task parameters; The task parameters include: Flyer number, production line number, task type, and material car number; The task execution information in JSON format includes: AGV number, task type, task target location, travel route, task priority, and other information; The task generation module is used to read information from the AGV status data table (AGV number, location coordinates, AGV status, task execution status, and task execution step data): First, determine whether the AGV has reached the production line. If it has, send a signal to the production line communication module. If the AGV has not reached the production line, send a signal to the data management module to update the AGV status data table and the material cart status data table. Then, it is determined whether the AGV task is completed. If the task is completed, a task completion string (JSON string) is generated and sent to the workshop control center API interface; if the task is not completed, a signal is sent to the data management module to update the AGV status data table and the material cart status data table. The task completion JSON string includes: task execution completion flag, AGV number, and task number; The task generation module is used to read the production line feedback information obtained by the production line communication module, generate a continue task instruction based on the production line feedback information, and send the continue task instruction to the AGV control system API interface. The production line feedback information includes: permission to enter and permission to leave; The continuation task instruction includes: AGV number and task number; The task instruction is a two-level nested JSON string task instruction; The task instruction types include: production line material feeding task instruction, production line material feeding task instruction, material cart transfer task instruction, scooter return task instruction, and material cart binding task instruction; The task instruction content includes: task number, map number, task type, location path, AGV number, material vehicle number, and request number; the material vehicle binding task instruction includes: request number, material vehicle number, AGV number, material vehicle location coordinates, material vehicle direction, and material vehicle binding flag; The location path includes: coordinates of the production line task point, coordinates of the production line material inlet, and coordinates of the target location; The material cart is a tool for loading AGVs to transport materials, and the AGV is a tool for carrying production materials to extract or unload processed materials on automated production lines. The data management module includes database interface tools and a digital twin model; The database interface tool is used to receive task execution status and AGV position data through the system interface module (AGV control system API interface), and write the task execution status and AGV position data into the material car status data table and the AGV status data table. When the AGV material transport vehicle arrives at the production line location, it provides feedback on the corresponding task execution status and message number. The data management module updates the task execution step information in the AGV status data table to 1. When the AGV material handling vehicle enters the production line and reaches the material inlet, the data management module updates the task execution step information in the AGV status data table to 2; When the AGV material handling vehicle leaves the production line material inlet and reaches the target location coordinates, the data management module updates the task execution step information in the AGV status data table to 0; The workshop digital twin model obtains the AGV scheduling scheme and sends the AGV scheduling scheme to the task generation module; The database interface tool of the data management module is a MySQL database table CRUD program written in Java, used to update and read data from the material cart status data table and the AGV status data table; the MySQL database table CRUD program written in Java is a Java database interface implementation class program based on the JPA framework, which includes full table data query, data addition, data update and deletion by specified ID in the material cart status data table and the AGV status data table.

[0020] The material cart status data table includes: material cart task, material and location information, including material cart number, flyer number, material cart location coordinates, task number, material cart direction, storage location and production line number; The AGV status data table includes: AGV task, status and location information, including: AGV number, AGV status, task number, IP address, battery level, material handling vehicle number, AGV direction, location coordinates, material handling vehicle direction, task execution status, task execution steps and message number.

[0021] The production line communication module includes: a TCP communication client and a control system; the production line communication module is used to establish a communication link between the automated workshop AGV intelligent transfer system and the automated production line control system, send queries to the automated production line control system and receive feedback. During the TCP communication client initialization phase, a communication link is established with the production line TCP server using the production line IP address and a specified communication port.

[0022] The communication link is a data interaction process under the TCP protocol between a TCP protocol communication client program written in JAVA and a TCP server on the production line; Sending queries to the automated production line control system includes: production line communication polling and production line querying; The production line communication polling specifically involves the TCP communication client sending a heartbeat communication code to the automated production line control system every 60 seconds and receiving feedback from the automated production line control system. a. If the production line communication module receives the heartbeat communication code from the automated production line control system, it means that the production line communication module and the automated production line control system are not disconnected. Wait 60 seconds and send the heartbeat communication code again. b. If the production line communication module does not receive the heartbeat communication code from the automated production line control system, it means that the production line communication module is disconnected from the automated production line control system. The initialized TCP communication client will attempt to connect to the production line TCP communication server. The production line inquiry includes: production line entry inquiry, production line entry report, production line exit inquiry, and production line exit report information; When the AGV material transport vehicle arrives at its designated location on the production line, the TCP communication client sends an entry query communication code to the automated production line control system and receives feedback from the automated production line control system: a) If the production line communication module receives a permission to enter the production line communication code from the automated production line control system, it sends the production line feedback permission to enter information to the task generation module. b) If the production line communication module receives a waiting entry communication code from the automated production line control system, it will wait 10 seconds and then send the entry inquiry communication code again. When the AGV material handling vehicle enters the production line and reaches the material inlet, the TCP communication client sends an "Entered Production Line" report communication code to the automated production line control system. After waiting 10 seconds, it sends a "Left Production Line" inquiry communication code to the automated production line control system and receives feedback from the automated production line control system. (a) If the production line communication module receives a permission to leave the production line communication code from the automated production line control system, it sends the production line feedback permission to leave information to the task generation module. (b) If the production line communication module receives a waiting to leave the production line communication code from the automated production line control system, it will wait 10 seconds and then send the leaving production line inquiry communication code again. When the AGV material handling vehicle leaves the production line and arrives at the material outlet, the TCP communication client sends a report communication code indicating that it has left the production line to the automated production line control system. The TCP communication client sends a 148-bit string of numbers to the automated production line control system, including: message header (2 bits), function bit (1 bit), task number (33 bits), AGV number (6 bits), reserved bit (3 bits), and batch number (103 bits). The function bit of the heartbeat communication code is 0, the function bit of the production line inquiry communication code is 1, the function bit of the production line entry report communication code is 2, the function bit of the production line exit inquiry communication code is 3, and the function bit of the production line exit report communication code is 4. The TCP communication client receives a 145-bit string of numbers from the automated production line control system, including the heartbeat communication code, permission to enter the production line communication code, waiting to enter the production line communication code, permission to leave the production line communication code, and waiting to leave the production line communication code. The string consists of: message header (2 bits), production line status bit (1 bit), reserved bit (2 bits), acknowledgment bit (1 bit), interval bit (4 bits), Fiorentina number (6 bits), and batch number (129 bits). The response bit of the heartbeat communication code is 0, the response bit of the allow-to-enter-the-production-line communication code and the allow-to-leave-the-production-line communication code is 1, and the response bit of the wait-to-enter-the-production-line communication code and the wait-to-leave-the-production-line communication code is 2.

[0023] The production line query is sent to the automated production line control system; at the same time, the production line communication module also receives feedback information from the automated production line control system.

[0024] Specific Implementation Method Two: The workshop data twin model is used to obtain the AGV scheduling scheme, specifically as follows: The aforementioned workshop data twin model is constructed in the following manner: First, create the workshop layout in Siemens PlantSimulation software; The workshop layout includes: all AGV running paths, the location of automated production lines, the location of material loading points on the production lines, the material storage area, the location of unloading points, and the distance between path points (the AGV running path consists of many path points, and each path point of the material cart corresponds to an AGV ground code. The AGV is positioned and moves by scanning the ground code, which is common industry knowledge). Then, the AGV is modeled: The attributes of the virtual AGV are set according to the AGV's operating speed, load capacity, battery capacity, shape and size, and position and angle parameters to ensure that the behavior of the virtual AGV is consistent with that of the physical AGV.

[0025] Finally, detailed attribute modeling was performed on elements such as automated production lines and material carts to establish the association between virtual AGVs and automated production lines and material cart models (when an AGV transports a material cart into the material inlet of the automated production line, the direction of the material cart and the direction of the material inlet must be consistent; at the same time, it must be ensured that the transported material cart belongs to the material cart used to transport materials of the current production line and must be consistent with the production line number in the material cart status table), forming a complete workshop data twin model; every 5 seconds, the PlantSimulation software obtains the latest position and status information of the AGV from the AGV status data table through the database interface tool, and then updates the virtual position and status of the AGV in the workshop twin model, so that the virtual model keeps synchronized with the physical workshop; The elements of the automated production line include: material inlet position and angle attributes, and material inlet shape and size attributes; The material cart elements include: material cart shape and size, and material cart position and angle; like Figure 5 As shown, the AGV scheduling scheme is obtained using EDA based on the workshop data twin model, specifically as follows: A1. Based on task requirements, task status, workshop layout, and AGV location information, construct the objective function and constraints, specifically as follows: Objective function: Minimize the total travel distance of the AGV in completing all tasks; The constraints include: Load constraint: The AGV's load capacity is less than the preset load limit; Material cart demand constraints: One material cart can only load and unload materials for one production line; Power constraint: The AGV's power supply must be greater than the power required to complete the task; A2. Initialize the iteration round t=1, initialize the population size N=500, the maximum number of iterations T=200, and the elite ratio. ; A3. Randomly generate N AGV scheduling schemes based on the constraints. Each AGV scheduling scheme is treated as an individual, forming a population. ; The scheduling scheme includes: task execution order, AGV number assigned to the task, material car number transported by the AGV, and AGV travel path information; A4. Population Each scheduling scheme is input into the workshop data twin model for simulation, thereby obtaining the logistics scheduling results; The logistics scheduling result refers to the travel path of the AGV to complete the task; A5. Obtain the fitness value of each individual based on the logistics scheduling results, select the best individuals based on the fitness value of each individual, and generate a probability matrix: First, The objective function value of the scheduling scheme corresponding to each individual is used as the fitness value of each individual; Then, sort each individual according to its fitness value from smallest to largest; Finally, take the former. Each individual is considered an excellent individual. The probability of the excellent individual's task allocation and path selection is calculated to generate a probability matrix. The probability matrix is ​​a probability distribution matrix; A6. Random sampling is performed in the probability matrix to generate N new individuals to form a new population. Random sampling is then performed in the new population. Individuals, will Individuals and A population is composed of outstanding individuals. ; During the sampling process, based on the probability distribution in the probability model, the task allocation and travel path planning of the AGV are randomly determined, and a new AGV scheduling scheme individual is generated.

[0026] A7. Obtaining the Population The fitness value of each individual is determined, and the individual with the minimum fitness value is selected as the population. To obtain the optimal individual population to population The fitness value corresponding to the best individual in each population is determined. If the number of consecutive individuals with the same fitness value exceeds L, it indicates that the current fitness value has converged, and the result is output. The best individual in the list is selected as the optimal scheduling scheme; otherwise, A8 is executed. The fitness value of an individual is the objective function value of the scheduling scheme corresponding to the current individual; This invention sets L=10; A8. Determine if the iteration number t is equal to T. If t is less than T, set t = t + 1 and return to A4; if t = T, output... The optimal individual in the process is used as the optimal scheduling scheme.

[0027] This invention relates to an automated workshop AGV intelligent transfer system, a computer program written in Java based on the Spring Boot Web architecture. Running on a workshop server, it connects and interacts with the workshop control center, automated production line control system, and AGV control system via network cable. The material cart is a steel material rack with wheels, capable of manual movement or transport by a stealthy transport robot. Materials to be processed are mounted on steel beam frame structures called "flying bars." The automated production line can use a lifting device at the material inlet to remove the flying bars and the materials mounted on them from the material cart or lower them onto an empty material cart. The AGV control system issues task instructions to the seven AGVs in the workshop. The specific task allocation scheme is planned by the workshop's digital twin model, and task instructions are generated through a task generation module and then sent to the AGV control system via its API interface for execution. The AGV control system feeds back the assigned AGV number and operating status to the system data management module to update the data in the AGV status data table. It supports a maximum of seven material transfer tasks simultaneously; the remaining tasks are cached in the AGV control system for later execution.

[0028] In this invention, operators issue material loading tasks, material handling tasks, or AGV return tasks to the workshop control center based on production tasks. After the production line finishes processing the materials, it generates unloading tasks and issues them to the workshop control center through the automated production line control system. In the case of adding new material cars or manually adjusting the position of material cars, operators need to issue material car binding tasks through the workshop control center to update the material car information in the AGV control system and the transfer system.

[0029] See Figure 2The automated workshop AGV intelligent transfer system and production line interaction process involves the task generation module triggering the production line communication module to send an access permission query code to the automated production line control system via a TCP communication client when the AGV material transport vehicle arrives at the production line. It then checks if the connection with the production line's TCP communication server is lost. If lost, the original TCP communication client is closed, the communication program memory is cleared, and the TCP communication client is reinitialized to attempt to connect to the production line's TCP communication server. If communication is normal, the response bit in the production line's reply code is parsed to determine if access is permitted. If not, the system waits 10 seconds and resends the access permission query code. If access is permitted, the task generation module generates a continuation task instruction and sends it to the AGV control system for execution. After the AGV material handling vehicle enters the production line material inlet, it updates the task execution steps and message number data in the AGV status data table with AGV task execution status data. The task generation module reads the AGV status data table and triggers the production line communication module to send an entry report communication code. Upon receiving a reply communication code from the production line, it sends a leave inquiry communication code and checks whether the connection with the production line's TCP communication server is lost. If the connection is lost, the original TCP communication client is closed, the communication program memory is cleared, and the TCP communication client is reinitialized to attempt to connect to the production line's TCP communication server. If communication is normal, the response bit in the production line's reply communication code is parsed to see if it allows leaving. If not, it waits 10 seconds and sends a leave permission inquiry communication code again. If leave is allowed, the task generation module generates a continue execution task instruction and sends it to the AGV control system for execution. The AGV material handling vehicle leaves the production line material inlet and heads to the target location coordinates in the task instruction, updating the task execution steps and message number data in the AGV status data table with AGV task execution status data. The task generation module reads the AGV status data table and triggers the production line communication module to send a leave report communication code.

[0030] See Figure 3The task execution process of the automated workshop AGV intelligent transfer system is as follows: Operators or production lines issue tasks to the workshop control center, forming task information. This task information is transmitted to the task generation module via the workshop control center API interface. The task generation module parses the task information and determines the task type. When the task type is a material cart binding task, the task generation module generates a material cart binding instruction based on the parsed task information. This instruction is then sent to the AGV control system via the AGV control system API interface for execution, and the module receives the execution results. The module updates the material cart status data table via the database interface tool of the data management module and reads the updated material cart status information, feeding it back to the workshop control center via the workshop control center API interface. When the task type is a material cart transfer task, production line loading task, production line loading task, or flyer return task, the task generation module parses the task information and reads the data from the material cart status data table, verifying the flyer information and production line information on the material cart, and then... The AGV scheduling scheme planned by the workshop digital twin model in the data management module generates corresponding task instructions and sends them to the AGV control system for execution through the AGV control system API interface of the system interface module. It receives and parses the JSON string containing AGV task execution information, and determines whether it has reached the production line based on the position coordinates and task execution status data in the feedback AGV execution status information. If it has reached the production line, it interacts with the automated production line control system through the production line communication module to control the AGV material transport vehicle to enter and leave the production line, and updates the AGV status data table and material vehicle status data table in the data management module. Before the AGV material transport vehicle reaches the target position coordinates, it continuously receives and parses the task execution status information fed back by the AGV control system to determine whether the AGV task has been completed. When the task is completed, the task generation module reads the data in the material vehicle status data table to generate task completion information, and feeds back the task completion information to the workshop control center through the workshop control center API interface.

[0031] When an AGV is performing a transport task, the system confirms the updated AGV status data table rows based on the feedback task number and AGV number, and updates the corresponding data table column values ​​accordingly. Similarly, the system confirms the updated material cart status data table rows based on the task number and material cart number, and updates the corresponding data table column values. When the AGV transports a material cart to the production line location, it provides feedback on the corresponding task execution status and message number, and the data management module updates the task execution step information in the AGV status data table to 1. When the AGV transports a material cart into the production line and reaches the material inlet, the data management module updates the task execution step information in the AGV status data table to 2. When the AGV transports a material cart away from the production line material inlet and reaches the target location coordinates, the data management module updates the task execution step information in the AGV status data table to 0. The task generation module triggers actions such as entering the production line inquiry, entering the production line report, leaving the production line inquiry, and task completion information feedback based on the task execution step data.

[0032] The production line communication module uses a TCP communication client to communicate with the automated production line control system via heartbeat communication to ensure a normal communication link. (See the process outlined below.) Figure 4 The flowchart describes the TCP communication initialization and heartbeat communication process of the production line communication module. When the automated workshop AGV intelligent transfer system starts operating, the production line communication module initializes the TCP communication client for each production line and connects to the production line TCP communication server according to the IP address and communication port of the automated production line control system, establishing a TCP communication link. Every 60 seconds, the TCP communication client sends a heartbeat code to the connected TCP communication server and waits to receive a reply heartbeat code from the TCP server. If no reply is received, the corresponding production line TCP communication client is closed, the communication program memory is cleared, the TCP communication client is reinitialized, and an attempt is made to establish a connection until the automated workshop AGV intelligent transfer system stops operating.

Claims

1. An automated workshop AGV intelligent transfer system, characterized in that... The system includes: a system interface module, a task generation module, a data management module, and a production line communication module; The system interface module includes: a workshop control center API interface and an AGV control system API interface; The workshop control center API interface is used to receive task information strings sent by the workshop control center and send the task information strings to the task generation module. The workshop control center API interface is used to receive task completion information from the task generation module when the AGV task is completed, and then send the task completion information to the workshop control center. The AGV control system API interface is used to receive task instructions and send them to the AGV control system. It also receives the task execution status and AGV position data fed back by the AGV system and sends them to the data management module. The task generation module is used to parse the task information string, receive the AGV scheduling scheme, convert the AGV scheduling scheme into the task execution information JSON format, read the task number and flyer number from the material car status data table, generate task instructions using the task information string parsing result, the task number and flyer number from the material car status data table, and the task execution information JSON format, and send the task instructions to the AGV control system API interface of the system interface module. The task generation module is used to read the information in the AGV status data table, and determine whether the AGV has arrived at the production line and whether the AGV task has been completed based on the information in the AGV status data table, and send signals to the production line communication module, workshop control center API interface or data management module. The task generation module is used to read the production line feedback information obtained by the production line communication module, generate a continue task instruction based on the production line feedback information, and send the continue task instruction to the AGV control system API interface. The data management module includes database interface tools and a digital twin model; The database interface tool is used to receive task execution status and AGV position data, and write the task execution status and AGV position data into the material car status data table and the AGV status data table. The workshop digital twin model obtains the AGV scheduling scheme and sends the AGV scheduling scheme to the task generation module; The production line communication module is used to establish a communication link between the automated workshop AGV intelligent transfer system and the automated production line control system, sending queries to the automated production line control system and receiving feedback.

2. The automated workshop AGV intelligent transfer system according to claim 1, characterized in that: The task information string is a 2-level nested JSON string, including: task number, request time and parameter information. The parameter information includes FIBA ​​number, production line number, material cart number, material cart position coordinates, material cart direction, task template number, target position coordinates and process number. The task completion information is a JSON string that includes a task completion flag, AGV number, and task number.

3. The automated workshop AGV intelligent transfer system according to claim 2, characterized in that: The task execution status reported by the AGV system includes: AGV number, AGV position coordinates, task number, material handling vehicle number, AGV direction, position coordinates, material handling vehicle direction, task execution status, and message number.

4. The automated workshop AGV intelligent transfer system according to claim 3, characterized in that: The parsed result of the task information string includes: task type and task parameters; The task parameters include: Flyer number, production line number, task type, and material car number; The task execution information in JSON format includes: AGV number, task type, task target location, travel route, and task priority.

5. The automated workshop AGV intelligent transfer system according to claim 4, characterized in that: The task generation module is used to read information from the AGV status data table, determine whether the AGV has arrived at the production line and whether the AGV task has been completed based on the information in the AGV status data table, and send signals to the production line communication module, the workshop control center API interface, or the data management module, specifically: First, determine whether the AGV has reached the production line. If it has, send a signal to the production line communication module; if the AGV has not reached the production line, send a signal to the data management module. Then, it is determined whether the AGV task is completed. If the task is completed, a task completion string is generated and sent to the workshop control center API interface; if the task is not completed, a signal is sent to the data management module.

6. The automated workshop AGV intelligent transfer system according to claim 5, characterized in that: The production line feedback information includes: permission to enter and permission to leave; The continued task instruction includes: AGV number and task number; The types of task instructions include: production line material feeding task instructions, production line material feeding task instructions, material cart transfer task instructions, scooter return task instructions, and material cart binding task instructions; The task instruction content includes: task number, map number, task type, location path, AGV number, material vehicle number, and request number; the material vehicle binding task instruction includes: request number, material vehicle number, AGV number, material vehicle location coordinates, material vehicle direction, and material vehicle binding flag; The location path includes: coordinates of the production line task point, coordinates of the production line material inlet, and coordinates of the target location.

7. The automated workshop AGV intelligent transfer system according to claim 6, characterized in that: The material cart status data table includes: material cart task, material and location information, including material cart number, flyer number, material cart location coordinates, task number, material cart direction, storage location and production line number; The AGV status data table includes: AGV task, status and location information, including: AGV number, AGV status, task number, IP address, power level, material handling vehicle number, AGV direction, location coordinates, material handling vehicle direction, task execution status, task execution steps and message number; The task execution steps in the AGV status data table include 1, 2, and 0; Where 1 indicates that the AGV transport vehicle has arrived at the production line position, 2 indicates that the AGV transport vehicle has entered the production line and reached the material inlet, and 0 indicates that the AGV transport vehicle has left the production line material inlet and reached the target position coordinates.

8. The automated workshop AGV intelligent transfer system according to claim 7, characterized in that: The production line communication module includes: a TCP communication client; Sending queries to the automated production line control system includes: production line communication polling and production line querying; The production line communication polling specifically involves the TCP communication client sending heartbeat communication codes to the automated production line control system at fixed time intervals, and then receiving feedback from the automated production line control system. a. If the production line communication module receives a heartbeat communication code from the automated production line control system, it means that the production line communication module and the automated production line control system have not lost connection. After waiting for the preset interval, the heartbeat communication code will be sent again. b. If the production line communication module does not receive the heartbeat communication code from the automated production line control system, it means that the production line communication module is disconnected from the automated production line control system. The initialized TCP communication client will attempt to connect to the production line TCP communication server. The production line query is sent to the automated production line control system, and the production line communication module also receives feedback information from the automated production line control system. The production line inquiry includes: production line entry inquiry, production line entry report, production line exit inquiry, and production line exit report information.

9. An automated workshop AGV intelligent transfer system according to claim 8, characterized in that: The production line inquiry includes: production line entry inquiry, production line entry report, production line exit inquiry, and production line exit report information, specifically: When the AGV material transport vehicle arrives at its designated location on the production line, the TCP communication client sends an entry query communication code to the automated production line control system, and then receives feedback from the automated production line control system: a) If the production line communication module receives a permission to enter the production line communication code from the automated production line control system, it sends the production line feedback permission to enter information to the task generation module. b) If the production line communication module receives a waiting entry communication code from the automated production line control system, it will wait for a preset time interval and then send the entry inquiry communication code again. When the AGV material handling vehicle enters the production line and reaches the material inlet, the TCP communication client sends an "Entered Production Line" report communication code to the automated production line control system. After waiting for a preset time interval, it sends a "Left Production Line" inquiry communication code to the automated production line control system and then receives feedback from the automated production line control system. (a) If the production line communication module receives a permission to leave the production line communication code from the automated production line control system, it sends the production line feedback permission to leave information to the task generation module. (b) If the production line communication module receives a waiting to leave the production line communication code from the automated production line control system, it will wait for a preset time interval and then send the leaving production line inquiry communication code again. When the AGV material handling vehicle leaves the production line and arrives at the material outlet, the TCP communication client sends a report communication code indicating that it has left the production line to the automated production line control system. The TCP communication client sends a 148-bit string of numbers to the automated production line control system, including: message header, function bits, task number, AGV number, reserved bits, and batch number. The message consists of: heartbeat communication code, entry inquiry communication code, entry report communication code, exit inquiry communication code, and exit report communication code. The function bit of the heartbeat communication code is 0, the function bit of the production line inquiry communication code is 1, the function bit of the production line entry report communication code is 2, the function bit of the production line exit inquiry communication code is 3, and the function bit of the production line exit report communication code is 4. The TCP communication client receives a 145-bit string of numbers from the automated production line control system, including the heartbeat communication code, permission to enter the production line communication code, waiting to enter the production line communication code, permission to leave the production line communication code, and waiting to leave the production line communication code. This string includes: message header, production line status bit, reserved bit, acknowledgment bit, interval bit, FIP number, and batch number. The response bit of the heartbeat communication code is 0, the response bit of the allow-to-enter-the-production-line communication code and the allow-to-leave-the-production-line communication code is 1, and the response bit of the wait-to-enter-the-production-line communication code and the wait-to-leave-the-production-line communication code is 2.

10. An automated workshop AGV intelligent transfer system according to claim 9, characterized in that: The workshop data twin model in the data management module is used to obtain the AGV scheduling scheme, specifically: A1. Construct the objective function and constraints, specifically as follows: The objective function is to minimize the total travel distance of the AGV in completing all tasks; The constraints include: load constraints, material cart demand constraints, and power constraints; The load constraint is that the AGV's load capacity is less than a preset load limit; The material cart requirement constraint is that one material cart can only load and unload materials for one production line. The power constraint is that the AGV's power is greater than the power required to complete the task; A2. Initialize the iteration round t=1, initialize the population size N, the maximum number of iterations T, and set the elite ratio. ; A3. Randomly generate N AGV scheduling schemes based on the constraints. Each AGV scheduling scheme is treated as an individual, forming a population. ; The scheduling scheme includes: task execution order, AGV number assigned to the task, material car number transported by the AGV, and AGV travel path information; A4. Population Each scheduling scheme is input into the workshop data twin model for simulation, thereby obtaining the logistics scheduling results; The logistics scheduling result refers to the travel path of the AGV to complete the task; A5. Obtain based on logistics scheduling results The fitness value of each individual is calculated, and excellent individuals are selected based on their fitness values, generating a probability matrix: First, The objective function value of the scheduling scheme corresponding to each individual is used as the fitness value of each individual; Then, sort all individuals according to their fitness values ​​from smallest to largest; Finally, take the former. Each individual is considered an excellent individual. The probability of the excellent individual's task allocation and path selection is calculated to generate a probability matrix. A6. Random sampling is performed in the probability matrix to generate N new individuals to form a new population. Random sampling is then performed in the new population. Individuals, will Individuals and A population is composed of outstanding individuals. ; A7. Obtaining the Population The fitness value of each individual is determined, and the individual with the minimum fitness value is selected as the population. To obtain the optimal individual population to population The fitness value corresponding to the best individual in each population is determined. If the number of consecutive individuals with the same fitness value exceeds L, it indicates that the current fitness value has converged, and the result is output. The best individual in the list is selected as the optimal scheduling scheme; otherwise, A8 is executed. The fitness value of an individual is the objective function value of the scheduling scheme corresponding to the current individual; A8. Determine if the iteration number t is equal to T. If t is less than T, set t = t + 1 and return to A4; if t = T, output... The optimal individual in the pool is used as the AGV scheduling scheme; The workshop data twin model is constructed in the following way: First, create the workshop layout in Siemens Plant Simulation software; The workshop layout includes: all AGV running paths, the location of automated production lines, the location of material loading points on the production lines, the material storage area, the location of unloading points, and the distances between path points; Then, the AGV is modeled: The attributes of the virtual AGV are set according to the AGV's operating speed, load capacity, battery capacity, shape, size, and position angle parameters to ensure that the behavior of the virtual AGV is consistent with that of the physical AGV. Finally, the automated production line and material cart elements are modeled, and the relationship between the virtual AGV and the automated production line and material cart model is established to obtain a workshop data twin model. The elements of the automated production line include: material inlet position and angle attributes, and material inlet shape and size attributes; The material cart elements include: material cart shape and size, and material cart position and angle; The specific relationship between the virtual AGV, the automated production line, and the material cart model is as follows: when the AGV transports the material cart into the material inlet of the automated production line, the direction of the material cart model is set to be consistent with the direction of the material inlet; at the same time, the material cart model is set as a material cart used to transport materials for the current production line.

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